The current invention utilizes a concept initially disclosed by the Inventor in his U.S. Pat. No. 6,179,431, filed Dec. 24, 1998. The difference between the invention described in the '431 patent and the current invention has to do with the use of a light emitting diode (LED) instead of an electro-luminescent element as the light source(s) of an emergency power failure night light, which operates on battery power when the supply of electricity to an electrical outlet is cut off during a power failure.
Also, a major difference between the LED night light of the invention and other conventional LED power failure night lights lies in power saving and management, eliminating the need to use relatively expensive and low-powered rechargeable batteries. All other prior art arrangements have preferred to use rechargeable batteries as the power source for the emergency light, which is very bad for at the reasons that:
(A) The capacity of the rechargeable battery normally is much less than that of a non-rechargeable battery. For example, a AAA size rechargeable battery only has a 650 ma capacity, while and the capacity of the non-rechargeable battery can be 1,000 ma to 1,200 ma for a Duracell brand battery, which is the most common battery used in North America. (B) Not only is there a big difference in the capacities of rechargeable and non-rechargeable batteries, but also in the potential risk for fire, which is larger for a rechargeable battery. It is common to hear that a cellular phone or flip top computer rechargeable battery has exploded, so it is dangerous to use a rechargeable battery for the power failure night light because, since the power failure night light is normally plugged into a wall outlet, if the inner rechargeable battery explodes, a big house fire can result, which might burn down the entire house or damage the electrical system, which might cost millions of dollars to repair. If any people are injured or die, the maker or seller will be held strictly liable.(C) To use a rechargeable battery as a power source for an emergency light incurs extra cost for the recharge circuit, and necessitates more safety electric components such as surge protection and high voltage impact protection to enable the circuit to survive a lightning strike on the house electric system, greatly increasing the overall cost of the rechargeable battery arrangement.(D) Still further, the rechargeable battery normally has a “memory” problem. If people do not initially plug-in the rechargeable battery device for at least 12 or more hours, the battery may only charge to ¼, ⅓, ½, ¾, or ⅔ of battery capacity (for example, 650 ma for a AAA battery, the battery can only be charged to 650/4, 650/3, 650/2, 650×¾, 650×⅔). No rechargeable battery has a 100% fully rechargeable quality.(E) The rechargeable battery degrades. Normally, the rechargeable battery can only be charged for a limited number of cycles and some batteries will degrade so quickly to degrading and that they can only be recharged 10, 50, or 100 times depending on which company makes the batteries.
Disadvantages (A), (B), (C), (D), (E) of rechargeable batteries are exacerbated because all current market power failure light use especially cheap China-made cheap rechargeable batteries without any well-known company to strictly test and endorse batteries. It is too big a risk to rely on such rechargeable batteries when they are needed during a power failure.
The current invention not only solves the most fatal concerns for rechargeable batteries as described above, but also optionally incorporates many of the advantageous features described in the above-cited applications and patents of the inventor, including provision of more than one light source, more than one function, more than one optics means, interchangeable power sources, a projection light, an LED light with special functions, and more than one reflective means.
According to the persistence of vision theory, the human eye has a response time within 1/24 (41.67 msec) to 1/16 (0.0625 sec) second, when an object moves faster than the human eye response time, the last image stays in the human eye and brain for a period of time. This theory can be applied to an LED or LEDs because an LED's or LEDs' response time is very short (around 10 msec or less). Hence, if more than 16-24 pictures per second appear in front of the human eye, than people will think all pictures are continuous. The current invention uses a related circuit, control means, IC, micro controller to make the LED or LEDs blink much faster than 16-24 times (cycles) per second with each cycle consisting of 10% turn-on and 90% for turn-off to thereby save 90% of the power consumption and increase battery life by nine times relative to a full steady-ON condition. This is a substantial power saving for all battery power source applications. It will be appreciated that new LED technology may coming soon to provide the LED with a quicker response time of less than 10 msec, and perhaps a 5 msec time or 2 msec to provide even more power saving. To adjust the duration time of each cycle for turn-on and turn-off will provide more power saving devices to meet the green world concept. This is the other very important concept of the current invention.
Further cost saving of a battery powered unit by using batteries which have a voltage that is lower than trigger voltage of the LED or LEDs and use a circuit with proper electric components, parts, and accessories to raise up the battery's lower voltage to a higher voltage to trigger the LED or LEDs. This can reduce the quantity of required batteries and further lower the cost of the battery operated LED light unit.
The above advantages may be achieved by providing the following combination of features:                An LED power failure device including:        at least one first LED element(s) that serves as a night light to offer illumination when its power source supplies an electric signal to the device from a preferred combination of power source and circuit means, switch means, sensor means, control means, and/or conductive means, the power source being connected by a USB adaptor or prong means;        at least one second LED element(s) that serves as an emergency light to offer illumination when the power source for the first LED or LEDs element(s) fails to supply an electric signal to the night light        wherein the second LED element(s) offer illumination from the battery power source when the first LED or LEDs element(s) power source fails to supply the electric signal to the device, the battery power source having a compartment that enables the battery or batteries to be easily replaced and installed, the battery being a non-rechargeable type,        the first LED element(s) and second LED element(s) having a desired number of pieces to offer sufficient light output and brightness for illumination and both element(s) being connected with a preferred combination of electric parts and accessories, switches, sensors, control means, diode(s), mechanical means, conductive means, an Integrated Circuit (IC), microcontroller, flip prong means, and USB connector to cause the night light and the emergency light to turn on and turn off according to a pre-determined function, time, brightness, color, timing, and/or direction.        
The LED power failure device may have more than one optics means Ser. No. 11/806,284, with the first LED elements being incorporated with an optics medium to cause the LED(s) to provide uniform area illumination when acting as a night light.
The LED power failure device may also have multiple light sources as described in the above-cited U.S. patent application Ser. No. 11/255,981, the first and second LED elements being arranged in a matrix to face at least one or multiple directions, or to have different positions, orientations, or locations to be seen by viewers, with some LED or LEDs acting as a night light and some acting as an emergency light.
The LED power failure device may also have multiple light sources such that the first and second LED light elements have LEDs that face in more than one direction, location, position, or orientation to offer multiple areas for illumination as described in U.S. patent application Ser. No. 11/255,981.
The LED power failure device may include first and second LED elements and at least one optics means selected from an optics lens, convex lens, concave lens, diffusion lens, curved lens, adjustable focus means, rotating or adjustable angle means, windows, openings, cutouts, or a reflector, to change optical properties of light beams emitted by the LED elements by, for example, magnifying a hot spot to provide wider area illumination, concentrating all LEDs light beams in a super bright spot, or creating other optical effects.
The LED power failure device may further include a mechanical or electric switch having at least one function selected from the following functions: on, off, auto, timer, time delay, flashing, partial on, partial off, partial flash, partial chasing, partial random, partial fade-in and fade-out, varied duration ON and OFF for the blinking function, power saving selection, blinking function selection, persistence of vision effects, blinking of an LED or LEDs, on and off percentage of each blinking cycle, power saving setting or selection, LED or LEDs group reset selection, or any LED light functions for a plurality of LEDs that are available from the market place.
The LED power failure device include first and second LED elements that, as disclosed in U.S. patent application Ser. No. 11/806,285, can be any type of LED with single color or multiple colors, including LEDs that change color, number of LEDs for illumination, and/or light functions by control, switch, or sensor means.
The LED power failure device may also be a multiple function LED light as disclosed in U.S. patent Ser. No. 11/806,285, in which the ordinary LED lighting functions are combined with other functions selected from the group of additional functions including functions of an electrical outlet, air freshener, motion sensor, beacon light, warning light, chasing lights, flash light, bug repelled device, mosquito repellant device, mouse repellant device, sonic repellant device, projection device, persistence of vision device, blinking LED device with or without different on and off percentages for each blinking cycle, power saving setting or selection devices, and devices with LED group reset selection for extra functions on the device.
The LED power failure device may also include multiple light sources as disclosed in U.S. patent application Ser. No. 11/255,981, the device having another LED or LEDs for indicating the battery status, including low battery capacity, full capacity, or half capacity with preferred colors to indicate the status of batteries, or show that the device is on duty status.
The LED power failure device may further include special effects, in which first and second LED element(s) are controlled by a control means to flash or blink at a rate that faster than a human's eye response time of 1/24 to 1/16 second to take advantage of the inertia of a human eye, the blinking speed meeting the requirement of persistence of vision to let the people see a continuous light beam from the LED element(s) to save power consumption of the batteries.
The LED power failure device may also have a blinking frequency that is faster than the human eye's scan speed, which is within 1/48 second, for a frequency of at least 48 Hz.
The LED power failure device may have a battery voltage that is higher than the LED trigger voltage, or a battery voltage that is lower than the LED trigger voltage while incorporating a voltage raise-up electric circuit to raise the battery voltage up to the LED trigger voltage.
The power saving features of the LED light device thus may be achieved by control means that cause the LED or LEDs to turn-on and turn-off for a certain percentage of each cycle take advantage of the persistence of vision of the human eye by turning off for less than 1/24 to 1/16 second to cause people to perceive the blinking LED or LEDs as being continuously on.